Wednesday, May 28, 2014

jQuery methods used to add new content

  • append() - Inserts content at the end of the selected elements
  • prepend() - Inserts content at the beginning of the selected elements
  • after() - Inserts content after the selected elements
  • before() - Inserts content before the selected elements

jQuery method attr(), with a callback function

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    $("#w3s").attr("href", function(i,origValue){
      return origValue + "/jquery";
    });
  });
});
</script>
</head>

<body>
<p><a href="http://www.w3schools.com" id="w3s">W3Schools.com</a></p>
<button>Change href Value</button>
<p>Mouse over the link (or click on it) to see that the value of the href attribute has changed.</p>
</body>
</html>

jQuery attr() method is also used to set/change attribute values.

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    $("#w3s").attr("href","http://www.w3schools.com/jquery");
  });
});
</script>
</head>

<body>
<p><a href="http://www.w3schools.com" id="w3s">W3Schools.com</a></p>
<button>Change href Value</button>
<p>Mouse over the link (or click on it) to see that the value of the href attribute has changed.</p>
</body>
</html>

Set Content - text(), html(), and val()

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("#btn1").click(function(){
    $("#test1").text("Hello world!");
  });
  $("#btn2").click(function(){
    $("#test2").html("<b>Hello world!</b>");
  });
  $("#btn3").click(function(){
    $("#test3").val("Dolly Duck");
  });
});
</script>
</head>

<body>
<p id="test1">This is a paragraph.</p>
<p id="test2">This is another paragraph.</p>
<p>Input field: <input type="text" id="test3" value="Mickey Mouse"></p>
<button id="btn1">Set Text</button>
<button id="btn2">Set HTML</button>
<button id="btn3">Set Value</button>
</body>
</html>

jQuery attr() method is used to get attribute values.

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    alert($("#w3s").attr("href"));
  });
});
</script>
</head>

<body>
<p><a href="http://www.w3schools.com" id="w3s">W3Schools.com</a></p>
<button>Show href Value</button>
</body>
</html>

jQuery val() method

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    alert("Value: " + $("#test").val());
  });
});
</script>
</head>

<body>
<p>Name: <input type="text" id="test" value="Mickey Mouse"></p>
<button>Show Value</button>
</body>
</html>

jQuery text() and html() methods

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("#btn1").click(function(){
    alert("Text: " + $("#test").text());
  });
  $("#btn2").click(function(){
    alert("HTML: " + $("#test").html());
  });
});
</script>
</head>

<body>
<p id="test">This is some <b>bold</b> text in a paragraph.</p>
<button id="btn1">Show Text</button>
<button id="btn2">Show HTML</button>
</body>
</html>